A non-contact reflection photoplethysmography (NRPPG) with its engineering model was created to access human
physiological information. The NRPPG engineering setup with a vertical cavity surface emitting laser (VCSEL) as a
light source and a high-speed PiN photodiode as a photodetector was configured based upon the principles of
light-tissue interaction and Beer-Lambert’s law. In this paper, we present three aspects of the NRPPG performance: (1)
photonics engineering work to capture photoplethysmographic signals with a non-contact manner in an optimal setup of
the NRPPG; (2) a 5-minute protocol with 22 participants to determine a good agreement between NRPPG and contact
photoplethysmography (CPPG) by means of Bland-Altman statistical analysis and Pearson’s correlation coefficient; and
(3) a physiological experiment designed for cardiac-physiological monitoring utilizing NRPPG. The experimental
results suggest that clean PPG signal can be obtained between 30-110 mm. The outcome from agreement study indicates
that the performance of NRPPG is compatible with CPPG. The NRPPG technique has great potential in
cardiac-physiological assessment in a required clinical circumstance
